You can use them how ever you like, edit them how ever you want, so long as you follow scirra's licencing.

You can use the sounds with other game engines as you please as well.

Use these sounds to improve the quality of your games before you release them. With a plenty selection of different varients of sounds for different applications you can even set them up to play them dynamically on different menus. Game modes, and should be able to have more than 1 sound for a single event like jumping or shooting with this sound pack.